| Abstract. Short chain fatty acids (SCFAs) are formed during bacterial fermentation of carbohydrates in the colon. One of these compounds, butyric acid is the main energy source for colonic cells and could prevent colon cancer. The aim of this research was to analyze short chain fatty acid profile (butyric, acetic, and propionic acid) produced by Clostridium butyricum during in vitro fermentation (37oC, anaerobic condition). Retrodegraded starch or resistant starch type III made from sweet potato was used as the fermentation substrate with different concentration (2%, 3%, and 5%). Sampling was done every 6 hours to determine bacterial growth (turbidimetry method), pH, and SCFA production (gas chromatograph-HP Innowax 19091N-136 column). The result showed that bacterial growth increased until 18-24 hours of fermentation, followed by pH reduction as the bacteria started to produce SCFA. The gas chromatography result showed that the highest concentrations of acetic acid, propionic acid, and butyric acid production were obtained from 2% substrate, but at different fermentation time for each compound. The highest production of butyric acid occurred at 18 hours of fermentation (198,41mmol/L), whereas butyric, propionic, and acetic acid proportion were 42:1:3. However, higher level of substrates did not increase SCFA production, probably due to metabolic pathway shift in SCFA production. |